How does Warfarin work in the body? What is a PT/INR?

A Coumadin Clinic just opened at the hospital across the street from my pharmacy. I am a new pharmacy tech, and I'm now entering a lot of (what seems like) funky weird warfarin prescriptions. For example, I recently filled an rx for warfarin 3.5mg every other day alternating with 4mg QOD. This means that I have to fill an rx for 2.5mg tablets and 1mg tablets to fill only one part of the rx. The other part is the 4mg tablets.

From what I understand, these patients of the Coumadin Clinic are monitored with a test/lab work called a PT/INR. What is this test and how does it relate to their warfarin dosing? And how does warfarin work in the body?

This page answers questions about Medicare Part D, the prescription drug benefit offered by Medicare. Topics include: Who is eligible? What are some of the Costs? Factors to Consider when choosing a p…